The field of the invention pertains to hollow articles such as containers and, in particular, bottles of flexible plastic construction, formed with a plurality of side wall bellows to permit collapse of the article. Examples of similar articles are disclosed in Diebolt et al U.S. Pat. No. 3,929,165 and French Patent No. 2,467,146, respectively. Typically at least one bellow, when axially urged, overcenters and latches itself in a collapsed state. To unlatch any collapsed bellow a pulling axial force need be exerted on the article.
Owing to the nature of the flexible plastic material used, an expanded article tends to wobble and as a result part of its contents may be spilled. Wobbling is apt to occur when the contents are hot.